Reduced keyboard character selection system and method

ABSTRACT

A system and method of selecting a letter for display in a communication device having a display and a reduced-key keyboard is provided. One of the plurality of keys on the reduced-key keyboard is selected and a default letter associated with the selected key is displayed. A backspace key is selected to display a cursor in the position of the default letter on the display. The key associated with the default letter is selected again and an alternate letter associated with the selected key is displayed in place of the default letter.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.12/204,632, filed Sep. 4, 2008, which is a continuation of U.S.application Ser. No. 11/733,111, (now U.S. Pat. No. 7,492,286), filedApr. 9, 2007, which is a continuation of U.S. application Ser. No.10/835,118, (now U.S. Pat. No. 7,224,292), filed Apr. 29, 2004.Application Ser. No. 12/204,632, application Ser. No. 11/733,111 andU.S. application Ser. No. 10/835,118 are expressly incorporated hereinby reference in their entirety.

FIELD

The technology described in this patent document relates generally tothe field of reduced-key keyboards. More particularly, a system andmethod of selecting a letter for display in a communication devicehaving a display and a reduced-key keyboard is described.

BACKGROUND

Keyboards (or keypads) having more than one letter key per physical keyare known. These types of keyboards are referred to herein asreduced-key keyboards. An alphanumeric phone pad is an example of such akeyboard. For example, the “2” key on a traditional phone pad has threeletters associated with it, the “A”, “B”, and “C” letters. One knowntechnique for making a letter selection in such a reduced-key keyboardis to link the number of times a key is consecutively selected with oneof the letter choices. Thus, in the case of the “2” key on the phonepad, a user would select the key once for the “A” letter, twice for the“B” letter, and three times for the “C” letter.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of an exemplary mobile communication devicethat may incorporate the system and method described herein;

FIG. 2 is an exemplary reduced-key QWERTY keyboard for use with themobile communication device shown in FIG. 1;

FIG. 3 is a sample flow diagram of a method of selecting a letterassociated with a reduced-key keyboard; and

FIG. 4 is another sample flow diagram of a method of selecting a letterassociated with a reduced-key keyboard.

DETAILED DESCRIPTION

Turning now to the drawing figures, which describe one example of theinvention described in this application, FIG. 1 is a block diagram of anexemplary mobile communication device that may incorporate the systemand method described herein. The mobile communication device 100includes a processing subsystem 138, a communications subsystem 111, ashort-range communications subsystem 140, a memory subsystem 124, 126,and various other device subsystems and/or software modules 142. Themobile communication device 100 also includes a user interface, whichmay include a display 122, a serial port 130, keyboard 132, a speaker134, a microphone 136, one or more auxiliary input/output devices 128,and/or other user interface devices.

The processing subsystem 138 controls the overall operation of themobile communication device 100. Operating system software executed bythe processing subsystem 138 may be stored in a persistent store, suchas a flash memory 124, but may also be stored in other types of memorydevices in the memory subsystem, such as a read only memory (ROM) orsimilar storage element. In addition, system software, specific deviceapplications, or parts thereof, may be temporarily loaded into avolatile store, such as a random access memory (RAM) 126. Communicationsignals received by the mobile communication device 100 may also bestored to RAM 126.

The processing subsystem 138, in addition to its operating systemfunctions, enables execution of software applications 124 on the device100. A predetermined set of applications that control basic deviceoperations, such as data and voice communications, may be installed onthe device 100 during manufacture. In addition, a personal informationmanager (PIM) application, including an electronic messagingapplication, may be installed on the device. The PIM may, fir example,be operable to organize and manage data items, such as email, calendarevents, voice mails, appointments, and task items. The PIM applicationmay also be operable to send and receive data items via the wirelessnetwork 119.

Communication functions, including data and voice communications, areperformed through the communication subsystem 111, and possibly throughthe short-range communications subsystem 140. The communicationsubsystem 111 includes a receiver 112, a transmitter 114 and one or moreantennas 116, 118. In addition, the communication subsystem 111 alsoincludes a processing module, such as a digital signal processor (DSP)120 or other processing device(s), and local oscillators (LOs) 113. Thespecific design and implementation of the communication subsystem 111 isdependent upon the communication network in which the mobilecommunication device 100 is intended to operate. For example, a mobilecommunication device 100 may include a communication subsystem 111designed to operate within the Mobitex.™. mobile communication system,the DataTAC.™. mobile communication system, a GSM network, a GPRSnetwork, a UMTS network, and/or an EDGE network.

Network access requirements vary depending upon the type ofcommunication system. For example, in the Mobitex and DataTAC networks,mobile communication devices are registered on the network using aunique personal identification number or PIN associated with eachdevice. In UMTS and GSM/GPRS networks, however, network access isassociated with a subscriber or user of a device. A GPRS devicetherefore requires a subscriber identity module, commonly referred to asa SIM card, in order to operate on a GSM/GPRS network.

When required network registration or activation procedures have beencompleted, the mobile communication device 100 may send and receivecommunication signals over the communication network 119. Signalsreceived by the antenna 116 from the communication network 119 arerouted to the receiver 112, which provides signal amplification,frequency down conversion, filtering, channel selection, etc., and mayalso provide analog to digital conversion. Analog-to-digital conversionof the received signal allows the DSP to perform more complexcommunication functions, such as demodulation and decoding. In a similarmanner, signals to be transmitted to the network 119 are processed(e.g., modulated and encoded) by the DSP 120 and are then provided tothe transmitter 114 for digital to analog conversion, frequency upconversion, filtering, amplification and transmission to thecommunication network 119 (or networks) via the antenna 118.

In addition to processing communication signals, the DSP 120 providesfor receiver 112 and transmitter 114 control. For example, gains appliedto communication signals in the receiver 112 and transmitter 114 may beadaptively controlled through automatic gain control algorithmsimplemented in the DSP 120.

In a data communication mode, a received signal, such as a text messageor web page download, is processed by the communication subsystem 111and input to the processing device 138. The received signal is thenfurther processed by the processing device 138 for output to a display122, or alternatively to some other auxiliary I/O device 128. A deviceuser may also compose data items, such as email messages, using akeyboard 138 and/or some other auxiliary I/O device 128, such as atouchpad, a rocker switch, a thumb-wheel, or some other type of inputdevice. The composed data items may then be transmitted over thecommunication network 119 via the communication subsystem 111. Thekeyboard 132 may be a reduced-key QWERTY keyboard, such as shown in FIG.2 below, in which there are fewer than 26 physical keys for receivinginput selections for each of the 26 letters of the English alphabet. Inthis type of keyboard, some of the keys are associated with more thanone character, examplarily letters. For example, the letters “D” and “F”occupy the same key in the keyboard shown in FIG. 2. For this keyboardlayout, the “D” key may be the default letter selected by the device 100when the key is selected and the “F” key may be an alternate letterselection. The methodology described below in connection with FIGS. 3and 4 may be programmed into software operating on the device 100 toenable selection of the alternative letter.

In a voice communication mode, overall operation of the device issubstantially similar to the data communication mode, except thatreceived signals are output to a speaker 134, and signals fortransmission are generated by a microphone 136. Alternative voice oraudio I/O subsystems, such as a voice message recording subsystem, mayalso be implemented on the device 100. In addition, the display 122 mayalso be utilized in voice communication mode, for example to display theidentity of a calling party, the duration of a voice call, or othervoice call related information.

The short-range communications subsystem 140 enables communicationbetween the mobile communication device 100 and other proximate systemsor devices, which need not necessarily be similar devices. For example,the short-range communications subsystem 140 may include an infrareddevice and associated circuits and components, or a Bluetooth.™.communication module to provide for communication with similarly-enabledsystems and devices.

Although the teachings of this application are described with referenceto the exemplary mobile communication device set forth in FIG. 1, it isto be understood that other types of mobile communication devices can beused, such as cellular telephones, two-way pagers, portable digitalassistants, etc.

FIG. 2 is an exemplary reduced-key QWERTY keyboard for use with themobile communication device shown in FIG. 1. The keyboard 132 preferablyutilizes five columns 302A-302E and four rows 300A-300D to represent areduced column QWERTY keyboard with an overlaid touch tone phone keyarrangement. The four rows 3001-300D include a first row 300A, a secondrow 300B, a third row 300C, and a fourth row 300D. The five columnsinclude a first column 302A, a second column 302B, a third column 302C,a fourth column 302D, and a fifth column 302E. FIG. 2 shows the touchtone phone key arrangement (numerals 1-9 and 0) as being centeredbetween the columns. The first row 300A of keys includes in order thefollowing key combinations, for the text entry and telephony mode: “QW”,“ER/1”, “TY/2”, “UI/3”, and “OP”. The second row 300B includes thefollowing key combinations in order: “AS/,”, “DF/4”, “GH/5”, “JK/6”, and“L/.”. The third row 300C includes the following key combinations inorder: “ZX/sym”, “CV/7”, “BN/8”, “M/9” and “backspace/delete.” The “sym”function key pulls up a list of symbols that the user may input. Thefourth row 300D includes the following key combinations in order: “alt”,“next/*”, “space/0”, “shift/#”, and “return (enter)”. The keys in thetop three rows 300A-300C are of uniform size while the keys in thefourth row 300D have a size that is different from the keys in the topthree rows. In particular, the center “space” key 304 is larger than theother four keys in the row, with the other four keys having a similarsize. The outermost keys in the fourth row 300D also have a more roundedshape, for aesthetic and other reasons. Each of the rows is straight andeach of the columns is straight, with the keys in the fourth row 300Dbeing mis-aligned with the five columns due to their different sizes.

In this reduced-key QWERTY keyboard 132, only two of the letter keys,the “L” and “M” letters are associated with a single physical key, theremaining letters are paired together and associated with a singlephysical key. Each physical key generates a single keystroke signal.Thus, if a user presses the “GH/5” key, it is not clear whether the usermeant to select the “G” key or the “H” key. Preferably, the device isprogrammed to select the “G” key as the default letter selection and the“H” key as the alternate letter selection.

FIG. 3 is a sample flow diagram 200 of a method of selecting a letterassociated with a reduced-key keyboard. The method may be used with amobile device 100 having a reduced-key QWERTY keyboard, for example,such as the keyboard 132 shown in FIG. 2, in which many of the keysinclude a default letter or character and at least one alternate letteror character selection. At step 202, the user of the device 100 selectsa letter key. The device then displays the default letter in step 204,which is typically the first letter associated with the selected key.For example, if the user selects the “D/F” key at column 302B and row300B of FIG. 2, the device will typically display the first letterassociated with that key as the default, which is the letter “D.” Theuser then selects another key at step 206. At step 208, the devicedetermines whether the user selected the backspace key 306 in step 206.If the user did not select the backspace key in step 206, then controlpasses back to step 204 and the default letter associated with theselected key is displayed. If, however, the user selected the backspacekey 306, then control passes to step 210 and the user selects anotherkey. The system then determines at step 212 if the user selected thesame key in step 210 that was selected in step 202. If the key selectedin step 212 is a different key than selected in step 202, then controlpasses to step 204 and the default letter associated with the selectedkey from step 212 is displayed in place of the default letter associatedwith the key selected in step 202. If, however, the user selected thesame key in step 212 that was selected in step 202, then the systemsubstitutes the alternate letter associated with the key selected instep 202 for the default letter in step 214 and control reverts to step202 for a new letter selection.

Although in some embodiments each key may have only a single defaultletter and a single alternate letter—i.e., two letters per key—in otherembodiments there may be more than two letters associated with some orall of the keys. In these embodiments, the system may perform anadditional step after step 212 in which the system determines which ofthe two or more alternate letters should be substituted for the defaultletter. Consider, for example, that the user has typed the lettersg-o-l-d, which form the word “gold.” The user then backspaces over the“d” letter and hits a key that has the letters d-e-f associate with it.In this situation, the system would consult a dictionary or otherdatabase to determine that it should substitute the letter “f” insteadof the letter “e” because of the probability that the user meant to type“golf” instead of “gole.”

Various types and forms of “backspace” keys can be used with themethodology described herein. In the example of FIG. 2, above, thebackspace key 306 is labelled with a back arrow symbol. In otherembodiments the “backspace” functionality can be implemented with othertypes and forms of keys, such as a “clear” key, which may be labelled“C” or “CLR,” for example. Other embodiments may include a soft keyassociated with a display screen, a touch screen key, or a navigationtool, such as a mouse or joystick selector.

FIG. 4 is another sample flow diagram 400 of a method of selecting aletter associated with a reduced-key keyboard. In this flow diagram,several letters have already been entered into the device 100. At step402, the user selects the backspace key 306 one or multiple times inorder to move a display cursor over a previously-selected letter. Instep 404, the user then selects the same key that caused thepreviously-selected letter to be displayed on the display. At step 406the system detects that the same key has been selected and analternative letter is substituted on the display for thepreviously-selected letter. The user then continues typing at step 408.For example, a user may have typed the letters C-O-N-C-E-R-T, butactually meant to type the word CONVERT. Using the method describedabove, the user would backspace the cursor until it was positioned atthe letter “C” between the letters “N” and “E” in the word CONCERT. Theletter “C” may be deleted when this backspace operation occurs, or itmay remain displayed but may be highlighted or otherwise modified insome manner. The user would then select the “C/V” key again, such asshown in FIG. 2 at column 302B and row 300C, which would cause thesystem to substitute the letter “V” on the display in place of theletter “C.” The user would then proceed to type the remain letters inthe word.

The above-described embodiments of the invention are intended to beexamples only. Those of skill in the art may effect alterations,modifications and variations to the particular embodiments withoutdeparting from the scope of the invention. For example, although thesystem and method are described in connection with a reduced-key QWERTYkeyboard having two letter keys per physical key, other keyboards couldbe used as well, such as phone-type keypads (non-QWERTY), or other typesof QWERTY style or other style alphabetic keyboards having at least onekey having a plurality of letters associated therewith. Other keyboardarrangements having multiple letters or characters per key may alsobenefit from the disclosed system and method of letter or characterselection. Moreover, although described with reference to an exampledevice as shown in FIG. 1, the methodology described herein can be usedwith any type of computing device having a reduced-key keyboard orkeypad.

1-12. (canceled)
 13. A mobile communication device comprising: adisplay; a keyboard having a plurality of input keys of which at leastone is a multi-character key having at least a default character and atleast one alternate character associated therewith, and a backspace key;a processing subsystem configurable to execute instructions fromsoftware applications stored on a memory subsystem, that when executed,the processing subsystem causes: displaying on the display the defaultcharacter associated with a selected one of the multi-character keys;deleting the default character on the display in response to receiving aselection of the backspace key; and based on a probability, displayingan alternate character associated with the multi-character key.
 14. Themobile communication device as recited in claim 13, wherein the defaultcharacter and the at least one alternate character associated with themulti-character key comprise a first letter and a second letter.
 15. Themobile communication device as recited in claim 14, wherein themulti-character key further comprises at least one numeric character.16. The mobile communication device as recited in claim 13, wherein thedefault character and the at least one alternate character associatedwith the multi-character key comprise at least one letter.
 17. Themobile communication device as recited in claim 16, wherein the defaultcharacter and the at least one alternate character associated with themulti-character key further comprises at least one numeric character.19. The mobile communication device as recited in claim 13, furthercomprising an enter key.
 19. The mobile communication device as recitedin claim 13, wherein the backspace key corresponds to one of a clearkey, a ‘C’ key, a ‘CLR’ key, a soft key, a touch screen key, anavigation tool, a mouse, and a joystick selector.
 20. The mobilecommunication device as recited in claim 13, wherein the softwareapplications further comprise instructions for positioning a cursor overthe alternate character on the display when a request to move the cursorto a previously entered character is received and to display a differentalternate character associated with the multi-character key in responseto receiving an additional selection of the multi-character key.
 21. Themobile communication device as recited in claim 13, wherein said displayis a touch screen.
 22. The mobile communication device as recited inclaim 21, wherein the keyboard is displayed by the touch screen.
 23. Themobile communication device as recited in claim 13, wherein the keyboardis a reduced-key keyboard having keys with a QWERTY alphabetic letterarrangement.
 24. The mobile communication device as recited in claim 23,wherein the QWERTY alphabetic letter arrangement comprises fourteenletter keys, the fourteen letter keys including twenty-six letterindicia.
 25. The mobile communication device as recited in claim 24,wherein the fourteen letter keys are organized into three rows of letterkeys, a first row comprising five letter keys, a second row comprisingfive letter keys and a third row comprising four letter keys.
 26. Themobile communication device as recited in claim 25, further comprising abackspace key positioned in the third row of letter keys.
 27. The mobilecommunication device as recited in claim 26, wherein the reduced-keykeyboard further comprises a numeric phone pad overlaid on the QWERTYalphabetic letter arrangement and centered on the three rows of letterkeys.
 28. The mobile communication device as recited in claim 23,wherein the reduced-key keyboard is a touch-tone phone pad.
 29. Themobile communication device as recited in claim 13, wherein displayingon the display the default character associated with one of themulti-character keys is in response to receiving a selection of themulti-character key.
 30. The mobile communication device as recited inclaim 13, wherein displaying one of the alternate characters associatedwith the multi-character key is in response to receiving a subsequentselection of the multi-character key.
 31. A method of selecting acharacter for display on a display of a communication device, saidcommunication device having a keyboard having a plurality of input keysof which at least one is a multi-character key having at least a defaultcharacter and at least one alternate character associated therewith, anda backspace key, the method comprising: displaying on the display thedefault character associated with a selected one of the multi-characterkeys; deleting the default character on the display in response toreceiving a selection of the backspace key; and based on a probability,displaying an alternate character associated with the multi-characterkey.
 32. The method as recited in claim 31, further comprisingpositioning a cursor over the alternate character on the display when arequest to move the cursor to a previously entered character is receivedand to display a different alternate character associated with themulti-character key in response to receiving an additional selection ofthe multi-character key.
 33. A method of selecting a character fordisplay in a communication device having a display screen and pluralityof user inputs including a reduced-key keyboard comprising a pluralityof input keys of which at least one is a multi-character key associatedwith a plurality of characters, the method comprising the steps of:selecting one of a plurality of input keys on the reduced-key keyboardand displaying a default character associated with the selected key;selecting at least one time a user input for inputting a request to movea cursor to a previously entered character and displaying the cursor ina position of the default character on the display screen; selecting theselected key; and based on a probability, displaying an alternatecharacter associated with the selected key.
 34. A processing subsystemconfigured to be installed in a mobile communication device comprising auser interface including a display screen and a plurality of user inputsincluding a reduced-key keyboard comprising a plurality of input keys ofwhich at least one is a multi-character key associated with a pluralityof alphanumeric characters, said processing subsystem comprising:control software programmed to display a default character associatedwith a selected multi-character key upon a first actuation thereof andto display a cursor in the position of the default character on thedisplay screen when a user input for inputting a request to move thecursor to a previously entered character is subsequently actuated atleast one time and to then display, based on a probability, an alternatecharacter associated with the selected multi-character key upon a secondactuation of the multi-character key.